Crosscompile
From DaphneWiki
Cross compiling
To build toolchain for raspberry pi, go here: http://www.bootc.net/archives/2012/05/26/how-to-build-a-cross-compiler-for-your-raspberry-pi/
Make sure to enable C++ (his instructions omit that part).
Zlib v1.2.7
The configure command is:
CHOST=arm-unknown-linux-gnueabi ./configure --prefix={pathtoyourxtools}/x-tools/arm-unknown-linux-gnueabi
then
make make install
expat v2.1.0
./configure --prefix={pathtoyourxtools}/x-tools/arm-unknown-linux-gnueabi --host=arm